Megan O’Flannery is a robotics expert and quite an insular person. When she’s offered a job at MindSim to develop a human-like, self-aware android, she doesn’t hesitate for long. MindSim has been developing them already but something has always gone wrong with the previous models. The newest, RS-4, also has problems which keep him from functioning fully. Megan starts to unravel them and finds out that while some of them are mechanical, there are also moral and ethical problems. MindSim is funded by the military and they want the android to become an assassin and a saboteur. Is it possible to make an artificial intelligence with a conscious and yet willingness to kill only the enemy?

She enlists the help of a reclusive and eccentric robotics genius, Chandrarajan Sundaram or Raj. However, when the android becomes more self-aware, he also seems to develop unhealthy attachments and hostilities. Megan and Raj are alone with RS-4, or Aris, in the secret underground laboratories in Nevada and when things start to go wrong they can’t contact anyone for help.

Aris is a very interesting thought experiment. He (apparently sexbots are female and killbots are male?) is supposed to pass for human but underneath his skin he has lots of mechanical parts and he even bleeds silver liquid which makes it easy to distinguish him from humans. His mind is made of complex programming and it includes a conscious, supposedly so that he wouldn’t kill and steal – except when the military tells him to. He also claims that he can’t feel any emotions and yet is strangely obsessed with sex and develops jealousy. However, at one time it seems that the “emotions” are just programmed responses and he doesn’t even understand them. Unfortunately, this isn’t explored further.

Megan is a workaholic but she has great taste in books; at one point she reads Lois McMaster Bujold’s Civil Campaign! She’s somewhat uncomfortable because she works for the military in order to give them, essentially, self-aware people who are stronger, smarter, and quicker than humans and yet they aren’t going to be given the same rights as humans to choose what to do with their lives. She wants androids to be given those rights, too.

Raj is very eccentric; apparently his mind works in different ways than most humans which makes him hard to understand. Also, he had a tough childhood which made him even more wary of people. Robots he understands and loves to work with them.

Most of the book has an action plot so musings about the android’s self-awareness isn’t the main thing and it could have been explored further. It also has a strong (and obvious) romance plot complete with a triangle which I didn’t care for.